The present invention relates to the packaging of integrated circuits (ICs) and more particularly to a method of making a stacked die package.
Stacked die packages are characterised by having two or more dice stacked within a single package. The stacking of two or more dice within a single package increases the functional integration of the package, without increasing its footprint. At present, dice in a stacked die package are typically either wirebond dice alone, or a combination of wirebond dice and a flip chip die. Most known methods of forming stacked flip chip packages are complicated and costly. Another drawback of existing methods is inflexibility in the sequence in which the dice are stacked. For example, some methods require dice of varying sizes be stacked from the largest at the bottom to the smallest on the top.
However, because of the advantages associated with the use of flip chip interconnections, semiconductor device manufacturers are currently developing methods of stacking multiple flip chip dice in a single package. It would be desirable to have a simple and inexpensive method of making a stacked package formed with only flip chip dice.